1. Technical Field
The present invention relates to optical devices.
2. Related Art
A surface-emitting type semiconductor laser has a characteristic in which its optical output changes depending on the ambient temperature. For this reason, an optical module that uses a surface-emitting type semiconductor laser may be equipped with a photodetecting function for detecting a portion of a laser beam emitted from the surface-emitting type semiconductor laser to monitor its optical output value. For example, a photodetector device such as a photodiode may be provided on a surface-emitting type semiconductor laser, whereby a portion of a laser beam emitted from the surface-emitting type semiconductor laser can be monitored within the same device. For example, Japanese laid-open patent application JP-A-10-135568 is an example of related art.